A key component of Singapore's new national digital identity (NDI) system for residents will be rolled out in the second half of this year.

The SingPass Mobile app will allow people to access e-government services more securely, and without the need for physical tokens and SMS one-time passwords (OTPs), said Dr Vivian Balakrishnan, Minister-in-charge of the Smart Nation Initiative in the Prime Minister's Office (PMO).

Ms Sun Xueling (Pasir Ris-Punggol GRC) and Ms Tin Pei Ling (MacPherson) had asked, during the debate on the PMO's budget, if recent SingPass outages would affect the reliability of the NDI.

Said Ms Tin: "How will the Government ensure NDI will be robust enough since citizens can use it to access services and potentially sensitive and personal information?"

Replying, Dr Balakrishnan, who is also Minister for Foreign Affairs, said: "A software bug in the recently upgraded system led to the crash. Unfortunately, this bug was in the backup system, too."

A comprehensive update will be provided when investigations are over, he added.

He assured the House that the Government imposes strict reliability and resiliency requirements for its critical systems and conducts regular and rigorous audits.

Asked about tangible outcomes from Singapore's Smart Nation efforts, Dr Balakrishnan said projects are on track.

For instance, the SingPass Mobile app will first go on trial in government departments this month.

To activate it, people need to register once with their existing SingPass credentials. To use the account, they will log in with their fingerprints or a user-determined six-digit pass code.

The app will provide a more secure and convenient way to access hundreds of e-government services, including the filing of income taxes, parking-fine payments and permit applications of foreign maids.

The NDI system also comprises a digital vault of personal data dubbed MyInfo, which "eliminates repetitive form-filling and document verification, and enhances accuracy", the minister said.

Since late last year, the 3.3 million SingPass users have been automatically enrolled in MyInfo.

It helps users to auto-fill forms for about 70 e-government services and 30 banking services such as opening a bank account.

Processing time for such applications has been reduced by 80 per cent, said Dr Balakrishnan, adding that more private-sector companies will be integrated later this year.